Recently, a wearable device has been used as a device for healthcare and fitness. The wearable device is mounted on a human body at, for example, an arm thereof, and measures a blood pressure, a pulse, a heart rate, the amount of activity, the number of steps, position information, and the like. The wearable device, which is used on the human body, has no display unit or an small display unit due to limitation on the size and weight thereof, which makes it difficult to display statistical data, for example.
Such a wearable device transmits measured data to a master device being paired through, for example, Bluetooth (registered trademark) (hereinafter also referred to as BT). Then, the master device manages the measured data by, for example, plotting of a graph of the measured data. Specifically, pairing is executed in advance between the wearable device and the master device such as a personal computer or a smartphone. The wearable device stores the measured data in a memory, for example, and transmits the measured data to the paired master device when communication is possible with the master device. Conventional technologies are described in Japanese National Publication of International Patent Application No. 2013-542510, for example.
However, when the wearable device is stolen or lost, data stored therein such as data measured by the wearable device and a user name set as an ID to the wearable device may be potentially leaked.
For example, the wearable device is not detected by other devices when pairing by BT is established, but is detectable by other devices when in a pairing mode as a connection standby state. The wearable device can be shifted to the pairing mode without limitation. A pairing code used by a device such as the wearable device during pairing is likely to be typically set to “0000” or “1234”, which makes pairing easy to be executed by a third party. These days, pairing can be executed through near field communication (NFC) by contacting devices with each other. For these reasons, a lost wearable device is potentially connected with a third-party device so that, for example, measured data of the wearable device is stolen.